In advertising various products, automobiles and other similar vehicles have been employed for carrying and displaying the advertisements. On automobiles these advertisements have typically been a single panel attached to the roof of the automobile extending substantially in a single plane from the front to the rear of the roof. To enhance the display of the advertisements the support structure for the panels have included devices for maintaining light bulbs to illuminate the panel. These light bulbs have been located exterior to and along the periphery of the panel which results in the panel being improperly lighted. Light bulbs supported in this manner create shadows on the panel detracting from its advertising effectiveness. Further, by having the light bulbs external to the panel they are easily damaged by weather and other wear including vandalism to which these devices are often subjected Also, by having the panels extend substantially in a single plane they cannot be properly viewed until the viewer is practically perpendicular to the plane of the panel.